New format type "select" in MessageFormatThe MessageFormat class will recognize a new format type "select". Just like for the format types "choice" and "plural", the format type is interpreted by creating a SelectFormat object from the subpattern string that's part of the element format definition.New class SelectFormatThe SelectFormat class is very similar to the PluralFormat class, with the following differences:
Use cases for select formatThe main use case for the select format is gender based inflection. When names or nouns are inserted into sentences, their gender can affect pronouns, verb forms, articles, and adjectives. Special care needs to be taken for the case where the gender cannot be determined. The impact varies between languages:
To enable localizers to create sentence patterns that take their language's gender dependencies into consideration, software has to provide information about the gender associated with a noun or name to MessageFormat. Two main cases can be distinguished:
{0} went to {2}.
The sentence pattern for French, where the gender of the person affects the form of the participle, uses a select format based on argument 1:
{0} est {1, select, female {allée} other {allé}} à {2}.
Patterns can be nested, so that it's possible to handle interactions of number and gender where necessary. For example, if the above sentence should allow for the names of several people to be inserted, the following sentence pattern can be used (with argument 0 the list of people's names, argument 1 the number of people, argument 2 their combined gender, and argument 3 the city name):
{0} {1, plural, one {est {2, select, female {allée} other {allé}}} other {sont {2, select, female {allées} other {allés}}}} à {3}.
The introduction of select formats and plural formats, and the possibly nested use of these formats, may result in rather complex message patterns. We have discussed this with localization vendors. They understand that the alternative, breaking down all the cases into separate individual strings, is not scalable. They believe that they can handle the syntax, although they were concerned about the ability of non-professional translators to handle it, and suggested validation in localization tools. They believe that developer's notes for the strings explaining variables and possible values of them will address most of the issues they're having. SelectFormat can also be used to handle article elision in French and a few other languages, where an article is contracted if the (immediately following) noun starts with a vowel or silent "h": "l’ami", "l’amie", "l’hache". To handle elision in addition to gender, the set of keywords to categorize nouns can be extended to "feminine", "masculine", "feminine-vowel", "masculine-vowel". A sample pattern would be: {1, select, feminine {La } masculine {Le } other {L’}}{0} est {1, select, feminine {petite} feminine-vowel {petite} other {petit}}. Open Design IssuesShould the keyword for the default case be "other" or "default"? Engineers are more used to "default", but PluralFormat set a different precedent by using "other".Should there be an API to return the set of keywords supported by a SelectFormat instance? This might help in the construction of a tool to collect and vet the information used by the SelectFormat. Parsing the pattern directly can be difficult because of pattern nesting and the painful quote rules for some formats. However, we'd have a better chance of getting the API supporting such a tool right if somebody actually worked on it. SelectFormat C++ APISelectFormat (const UnicodeString &pattern, UErrorCode &status)Creates a new SelectFormat for a given pattern string. SelectFormat (const SelectFormat &other)Copy constructor. virtual ~ SelectFormat ()Destructor. void applyPattern (const UnicodeString &pattern, UErrorCode &status)Sets the pattern used by this select format. UnicodeString &toPattern (UnicodeString &appendTo)Returns the pattern from applyPattern() or constructor(). UnicodeString &format (const UnicodeString &keyword, UnicodeString &appendTo, FieldPosition &pos, UErrorCode &status) constFormats a select message for a given keyword. UnicodeString &format (const Formattable &obj,
UnicodeString &appendTo, FieldPosition &pos, UErrorCode
&status) constRedeclared Format method. virtual void parseObject (const UnicodeString &source, Formattable &result, ParsePosition &parse_pos) constThis method is not supported by SelectFormat. SelectFormat &operator= (const SelectFormat &other)Assignment operator. virtual UBool operator== (const Format &other) constReturn true if another object is semantically equal to this one. virtual UBool operator!= (const Format &other) constReturn true if another object is semantically unequal to this one. virtual Format *clone (void) constClones this Format object polymorphically. virtual UClassID getDynamicClassID () constICU "poor man's RTTI", returns a UClassID for the actual class. static UClassID getStaticClassID (void)ICU "poor man's RTTI", returns a UClassID for this class. SelectFormat Java APISelectFormat(String pattern)Creates a new SelectFormat for a given pattern string. void applyPattern(String pattern)Sets the pattern used by this select format. String toPattern() Returns the pattern for this SelectFormat. StringBuffer format(Object keyword, StringBuffer toAppendTo, FieldPosition pos) Selects the phrase for the given keyword. String format(String keyword) Selects the phrase for the given keyword. Object parseObject(String source, ParsePosition pos) This method is not supported by SelectFormat. boolean equals(Object obj)Indicates whether some other object is "equal to" this one. int hashCode()Returns a hash code value for the object. String toString() Returns a string representation of the object. |
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